Various types of life jackets are known in the prior art. However, what has been needed is a life jacket having at least one belt in combination with a releasable buckle, the releasable buckle having a female member and a male member. Each of the female member and the male member has a top side and a bottom side. The female member is configured to securely engage the male member. What has been further needed is an opening continuously disposed through the male member from the top side to the bottom side and an aperture continuously disposed through the female member from the top side to the bottom side. Lastly, what has been needed is for a U-lock to slidingly engage the opening in combination with the aperture when the female member is securely engaged with the male member. The U-lock can optionally be a buoyant plastic. The U-lock is thus configured to lock the male member with the female member, which will prevent a child from removing the life vest without adult supervision or consent.